乳清蛋白及其水解物对马铃薯淀粉体外消化性和理化性质的影响

本文通过构建乳清蛋白及乳清蛋白水解物与马铃薯淀粉的共糊化体系来探究乳清蛋白及其水解物对马铃薯淀粉体外消化性和理化性质的影响。结果表明，经过胃蛋白酶和胰酶水解处理的乳清蛋白水解物对淀粉的消化率抑制效果最为明显。其中，天然马铃薯淀粉中快消化淀粉（RDS）含量最高（94.54%），抗性淀粉（RS）含量最低（3.10%）。而经过胃蛋白酶处理后经胰酶处理120 min的样品中的RDS含量最低（67.51%），RS含量最高（12.69%）。乳清蛋白水解物对马铃薯淀粉的溶胀和糊化的抑制作用均强于乳清蛋白。这说明乳清蛋白水解物的分子量对马铃薯淀粉的理化特性和消化性均有较大影响。此外，乳清蛋白及其水解物增强了体系中的氢键作用并提高了淀粉结构的有序程度，表明乳清蛋白及其水解物与马铃薯淀粉之间的相互作用会降低淀粉的消化性。

Effects of Whey Protein and Its Hydrolysates on in Vitro Digestibility and Physicochemical Properties of Potato Starch

The effect of whey protein and its hydrolysates on the in vitro digestibility and physicochemical properties of potato starch (PS) was investigated by constructing the co-gelatinization system between the PS and whey protein or whey protein hydrolysates. The results showed that whey protein hydrolysates hydrolyzed by pepsin-pancreatin (WPP) had the best inhibitory effect on the digestibility of starch. Thereinto, the native PS displayed the highest rapidly digestible starch (RDS) content (94.54%) and lowest resistant starch (RS) content (3.10%). Lower RDS (67.51%) and higher RS (12.69%) contents were found for PS-WPP120 complex. The inhibitory effect of whey protein hydrolysates on the swelling and gelatinization of PS was stronger than that of whey protein. Therefore, the molecular weight of whey protein hydrolysates had a notable influence on both physicochemical properties and in vitro digestibility. And whey protein or its hydrolysates strengthened the hydrogen bonding and increased the order degree of PS structure, indicating that the interactions between PS and whey protein or whey protein hydrolysates could reduce in vitro digestibility of PS.